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基于第一性原理C-Cd掺杂ZnO的电子结构和光学性质的研究

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原子与分子物理学报 2025年第2期42卷 135-142页

作者：张善祥李海侠于镇吴浩伟张巍钟桂林理工大学广西高校先进制造与自动化技术重点实验室桂林541006 桂林理工大学机械与控制工程学院桂林541006

借助于计算材料科学和化学的计算机模拟软件Materials Studio,利用密度泛函理论下的第一性原理的计算方法,系统的计算研究了C、Cd单掺杂以及C和Cd共掺杂(不同浓度)ZnO的形成能、电子结构和光学性质.计算结果表明:单掺杂体系当中,C掺杂... 详细信息

借助于计算材料科学和化学的计算机模拟软件Materials Studio,利用密度泛函理论下的第一性原理的计算方法,系统的计算研究了C、Cd单掺杂以及C和Cd共掺杂(不同浓度)ZnO的形成能、电子结构和光学性质.计算结果表明:单掺杂体系当中,C掺杂时形成能是正的,说明掺杂体系不易形成;共掺杂体系当中,所有掺杂体系的形成能均为负的,C-2Cd掺杂时形成能最低;与本征ZnO相比,所有掺杂体系的禁带宽度均有所降低,由于C元素的掺杂,禁带中产生杂质能级,减小电子跃迁所需要的能量;在光学性质方面,所有掺杂体系在低能区域的吸收图谱、介电函数虚部的峰值与本征ZnO相比均有所增大,且在低能区均发生红移,其中C-2Cd掺杂体系的红移程度最为明显且峰值最大.由此说明C和Cd共掺杂有望提高ZnO的光吸收率和光电转化效率,可以扩展其在光电器件领域中的应用.

关键词： C-Cd共掺杂第一性原理密度泛函理论电子结构光学性质

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基于第一性原理的Sc掺杂ZnO对气体的吸附特性研究

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原子与分子物理学报 2025年第1期42卷 54-60页

作者：张巍钟李海侠吴浩伟于镇张善祥桂林理工大学广西高校先进制造与自动化技术重点实验室桂林541006 桂林理工大学机械与控制工程学院桂林541006

CO、SO_(2)、H_(2)S是矿井内由煤炭及围岩中涌出或在生产过程中产生的的典型有毒气体,本文采用第一性原理及密度泛函理论研究了稀土元素Sc掺杂ZnO对单个气体分子(CO、SO_(2)、H_(2)S)的吸附特性.通过对各体系布居分布、能带结构、态密... 详细信息

CO、SO_(2)、H_(2)S是矿井内由煤炭及围岩中涌出或在生产过程中产生的的典型有毒气体,本文采用第一性原理及密度泛函理论研究了稀土元素Sc掺杂ZnO对单个气体分子(CO、SO_(2)、H_(2)S)的吸附特性.通过对各体系布居分布、能带结构、态密度及差分电荷密度分析,研究结果表明:Sc-ZnO(001)-Zn位掺杂体系稳定性最好,Sc-ZnO对单个CO、SO_(2)及H_(2)S分子的吸附能分别为-0.140 eV、-1.885 eV及-0.093 eV,其中对SO2分子的吸附为化学吸附,其余为物理吸附.确定了Sc-ZnO作为半导体气敏传感器来检测三种有毒气体的可行性,尤其是对于SO_(2)气体,为Sc-ZnO作为气敏传感材料实现对矿井有毒气体的检测提供了理论指导.

关键词：第一性原理 Sc掺杂ZnO 有毒气体吸附特性

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Cysteinyl leukotriene receptor 1 is involved in N-methyl-D-aspartate-mediated neuronal injury in mice

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Acta Pharmacologica Sinica 2006年第12期27卷 1526-1536页

作者： Qian DING Er-qing wei~2 Yan-jun zhang wei-ping zhang zhong CHEN Department of Pharmacology,School of Medicine,Zhejiang University,Hangzhou 310058,China Department of Pharmacology School of Medicine Zhejiang University Hangzhou China

Aim:To determine whether cysteinyl leukotriene receptor 1(CysLT1receptor)isinvolved in N-methyl-D-aspartate(NMDA)-induced excitotoxic injury in the ***:Brain injury was induced by NMDA microinjection(50-150 nmolin 0.5 μL)into the cerebral *** changes in CysLT1receptor expression24 h after NMDA injection and the effects of a CysLT1receptor antagonist,pranlukast(0.01 and 0.1 mg/kg),an NMDA receptor antagonist,ketamine(30mg/kg),and an antioxidant,edaravone(9 mg/kg)were ***:In theNMDA-injured brain,the CysLT1receptor mRNA,and protein expression wereupregulated,and the receptor was mainly localized in the neurons and not in ***,ketamine and edaravone decreased NMDA-induced injury;pranlukast(0.1 mg/kg)and ketamine inhibited the upregulated expression of ***:CysLT1receptor expression in neurons isupregulated after NMDA injection,and NMDA-induced responses are inhibitedby CysLT1receptor antagonists,indicating that the increased CysLT1receptor isinvolved in NMDA excitotoxicity.

关键词： cysteinyl leukotriene receptor excitotoxicity N-methyl-D-aspartate leukotriene receptor antagonist pranlukast NMDA receptor antagonist ketamine

Laparoscopic surgery in the mainland of China

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Chinese Medical Journal 2009年第19期122卷 2226-2228页

作者： GUO wei zhang zhong-tao Department of General Surgery Beijing Friendship Hospital Capital Medical University Beijing 100050 China

Laparoscopic surgery in the mainland of China began ,in 1991, when Dr. XUN Zu-wu from the Second Hospital of Qujing City in Yunnan Province successfully performed the first laparoscopic cholecystectomy （LC）. From then on, the implementation of laparoscopic techniques has been increased rapidly all over China. These techniques have been used nearly in all fields of general surgery including colorectal, gastric, hepatic, pancreatic, thyroid and mammary surgeries.

关键词： laparoscopic cholecystectomy Yunnan Province implementation techniques China

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基于最小二乘支持向量机的比特分配算法

电子学报 2007年第4期35卷 756-760页

作者：张忠伟中国科学院空间科学与应用研究中心北京100080

Q2算法是新一代国际视频编码标准MPEG-4的标准码率控制算法,但在低码率和低延迟的实时视频通信中,Q2算法往往会导致编码图像质量产生剧烈的波动,大大降低了信宿端重建视频的视觉效果.为此,本文从机器学习的角度出发,提出了一种以最小二... 详细信息

Q2算法是新一代国际视频编码标准MPEG-4的标准码率控制算法,但在低码率和低延迟的实时视频通信中,Q2算法往往会导致编码图像质量产生剧烈的波动,大大降低了信宿端重建视频的视觉效果.为此,本文从机器学习的角度出发,提出了一种以最小二乘支持向量机在线建模的比特分配算法,用新算法取代Q2中的比特分配算法,设计出一个改进的Q2码率控制方案.实验仿真结果表明:与原始Q2方案相比,改进后的Q2码率控制方案取得了更加平稳、更加均衡的图像质量,极大地提高了视频通信的视觉质量.

关键词： MPEG-4 码率控制最小二乘支持向量机目标比特分配

A Tensor-based Enhancement Algorithm for Depth Video

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科技视界 2018年第5期 79-81页

作者： YAO MENG-qi zhang wei-zhong College of Computer science and Technology Qingdao University

In order to repair the dark holes in Kinect depth video, we propose a depth hole-filling method based on ***, we process the original depth video by a weighted moving average system. Then, reconstruct the low-rank sensors and sparse sensors of the video utilize the tensor recovery method, through which the rough motion saliency can be initially separated from the background. Finally, construct a four-order tensor for moving target part, by grouping similar patches. Then we can formulate the video denoising and hole filling problem as a low-rank completion problem. In the proposed algorithm, the tensor model is used to preserve the spatial structure of the video modality. And we employ the block processing method to overcome the problem of information loss in traditional video processing based on frames. Experimental results show that our method can significantly improve the quality of depth video, and has strong robustness.

关键词： Depth video Ttensor Tensor recovery Kinect

QTL consistency for agronomic traits across three generations and potential applications in popcorn

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Journal of Integrative Agriculture 2015年第12期14卷 2547-2557页

作者： DONG Yong-bin zhang zhong-wei SHI Qing-ling WANG Qi-lei ZHOU Qiang DENG Fei MA Zhi-yan QIAO Da-he LI Yu-ling College of Agronomy Henan Agricultural University/Collaborative Innovation Center of Henan Grain Crops/National Key Laboratory of Wheat and Maize Crop Science

Favorable agronomic traits are important to improve productivity of popcorn. In this study, a recombinant inbred line（RIL） population consisting of 258 lines was evaluated to identify quantitative trait loci（QTLs） for nine agronomic traits（plant height, ear height, top height（plant height subtracted ear height）, top height/plant height, number of leaves above the top ear, leaf area, stalk diameter, number of tassel branches and the length of tassel） under three environments. Meta-analysis was conducted then to integrate QTLs identified across three generations（RIL, F2：3 and BC2F2） developed from the same crosses. In total, 179 QTLs and 36 meta-QTLs（m QTL） were identified. The percentage of phenotypic variation（R2） explained by any single QTL varied from 3.86 to 28.4%, and 24 QTLs with contributions over 15%. Nine common QTLs located in the same or similar chromosome regions were detected across three generations. Five meta-QTLs were identified including QTLs in three independent studies. Seven important m QTLs were composed of 11–26 QTLs for 4–7 traits, respectively. Only 11 m QTLs were commonly identified in the same or similar chromosome regions across agronomic traits, popping characteristics（popping fold, popping volume and popping rate） and grain yield components（ear weight per plant, grain weight per plant, 100-grain weight, ear length, kernel number per row, ear diameter, row number per ear and kernel ratio） by meta-QTL analysis. In conclusion, we identified a list of QTLs, some of which with much higher contributions to agronomic traits should be valuable for further study in improving both popping characteristics and grain yield components in popcorn.

关键词： popcorn agronomic traits quantitative trait locus(QTL) meta-analysis

Overview of Camera Calibration

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科技信息 2013年第7期 293-295页

作者： YANG Fei zhang wei-zhong HAN Wen-xi zhang Feng College of Information Engineering Qingdao University Qingdao Shandong 266071

This paper introduce several commonly used camera calibration method include their advantages and *** traditional methods of camera calibration need to know precise structural information of calibration object and they are *** calibration based on active vision get the camera calibration through the controlling of some parameters of ***-calibration of camera don't need to use the calibration block and get the camera calibration through the corresponding relationship among multiple images.

关键词：英语学习学习方法阅读知识阅读材料

A Comparison of Brain Death Criteria between China and the United States

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Chinese Medical Journal 2015年第21期128卷 2896-2901页

作者： Ze-Yu Ding Qian zhang Jian-wei Wu zhong-Hua Yang Xing-Quan Zhao Department of Neurology Beijing Tiantan Hospital Capital Medical University China National Clinical Research Center for Neurological Diseases Center of Stroke Beijing Institute for Brain Disorders Beijing Key Laboratory of Translational Medicine for Cerebrovascular Disease Beijing 100050 China

Background： Criteria for determining brain death （BD） vary between China and the United States. We reported the results of an investigation designed to compare procedures to determine BD in two countries. Methods： The latest criteria in the United states were published in 2010. The latest criteria in China were published in 2009. We used these two types of BD criteria to evaluate patients who were considered to be BD. The time, cost, and accuracy of the diagnosis were compared. Results： From January 1, 2012 to October 8, 2013, there were 37 patients which were applied for BD evaluation in the Neurological Intensive Care Unit of Beijing Tiantan Hospital. The cause of coma were known as subarachnoid hemorrhage （18 patients, 48.6%）, intracerebral hemorrhage （8 patients, 21.6%）, cerebral ischemia （9 patients, 24.3%）, brain stem tumor （1 patient, 2.7%）, and intracranial infection （1 patient, 2.7%）. The clinical examinations were done for all of the patients except 1 patient who had low blood pressure. Three patients had hrainstem reflexes that were excluded from BD. Twenty-five patients had apnea tests, and 20 tests were completed that were all positive. Confirmatory tests were completed differently： Transcranial Doppler （30 patients, positive rate 86.7%）, electroencephalogram （25 patients, positive rate 100%）, and somatosensory evoked potential （16 patients, positive rate 100%）. Thirty-three patients were diagnosed BD by criteria of the United States. Only 9 patients were diagnosed BD by Chinese criteria. The use of time and money in the USA criteria was obviously fewer than those in Chinese criteria （P = 0.000）. Conclusion： Compared with BD criteria of the United States, Chinese criteria were stricter, lower positive rate, more cost in money and time, and more reliable by families and doctors.

关键词： Apnea Test Brain Death Criteria China Diagnosis the United States